Royal Entomological Society HANDBOOKS FOR THE IDENTIFICATION OF BRITISH INSECTS To purchase current handbooks and to download out-of-print parts visit: http://www.royensoc.co.uk/publications/index.htm This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 UK: England & Wales License. Copyright © Royal Entomological Society 2012 ROYAL ENTOMOLOGICAL SOCIETY OF LONDON Vol. VIII. Part 3 (dii). HANDBOOKS FOR THE IDENTIFICATION OF BRITISH INSECTS HYMENOPTERA PROCTOTRUPOIDEA DIAPRIIDAE subfamily BELYTINAE By G. E. J. NIXON. LONDON Published by the Society and Sold at its Rooms 41, Queen's Gate, S.W. 7 31st December, 1957 Price 2os. od. HANDBOOKS FOR THE IDENTIFICATION OF BRITISH INSECTS The aim of this series of publications is to provide illustrated keys to the whole of the British Insects (in so far as this is possible), in ten volumes, as follows : I. Part 1. General Introduction. Part 9. Ephemeroptera. , 2. Thysanura. , 10. Odonata. , 3. Protura. , 11. Thysanoptera. , 4. Collembola. , 12. Neuroptera. , 5. Dermaptera and , 13. Mecoptera. Orthoptera. , 14. Trichoptera. , 6. Plecoptera. , 15. Strepsiptera. , 7. Psocoptera. , 16. Siphonaptera. , 8. Anoplura. Il. Hemiptera. Ill. Lepidoptera. / IV. and V. Coleoptera. VI. Hymenoptera : Symphyta and Aculeata. VII. Hymenoptera : lchneumonoidea. VIII. Hymenoptera: Cynipoidea, Chalcidoidea, and Serphoidea. IX. Diptera: Nematocera and Brachycera. X. Diptera : Cyclorrhapha. Volumes 11 to X will be divided into parts of convenient size, but it is not possible to specify in advance the taxonomic content of each part. Conciseness and cheapness are main objectives in this new series, and each part will be the work of a specialist, or of a group of specialists. Although much of the work will be based on existing published keys, suitably adapted, it is expected that it will also include much new and original matter. Parts will be issued, separately paged and priced, as they become available. Orders for the Series or for separate parts may be placed with the - Registrar at the Society's rooms now, but prices can only be quoted for those parts already in the press. - The Society is indebted to the Royal Society for a grant towards the cost of initiating this series of Handbooks. A list of parts now available appears on the back cover HYMENOPTERA PROCTOTRUPOIDEA. Dl:APRUDAE, Subfamily BELYTINAE. By G. E. J~ NIXON. INTRODUCTION, THE Diapriidae, as interpreted by Kieffer in Das Tierreich, Diapriidae (1916), are divided into two subfamilies, the Diapriinae and the Belytinae. These have been accorded family rank by some authors but Muesebeck and Walkley, whose nomenclature as set out in the Synoptic cata"Wgue of the Hymenoptera of America N. of Mexico (1951) has, in the main, been followed, prefer to retain the lower status for them. This. Handbook sets a precedent in that it covers rather more than the British fauna and also includes new genera and species. The reason for this was in part a serious lack of British material, offset on the other hand by the availability in the British Museum of a magnificent collection frpm South Sweden. Comprising some 5000 specimens of Belytinae, this collection was made by Mr. and Mrs. J. F. ~erkins in 1938. It proved indispensable to a stu4y of the British fauna and not to have worked it out as a whole would have been, in my opinion, a serious mistake. It therefore became the basis of this synopsis, giving it a wider scope than was originally intended without, it is hoped, diminishing its usefulness to British entomologists. The descriptions of new species appear in the keys but new genera are described separately. With regard to the new species, every structural feature that I believe to be important has been mentioned either in the framework of the key itself or within brackets immediately in association with each new name: . The keys are original and based only on specimens that I have personally examined. They cannot be expected to lead to positive results unless used in conjunction with the figures. In the keys the names of species not recorded from Britain are printed in a distinguishing type. TERMINOLOGY. The nomenclature of the wing venation is that used by Kieffer in his monograph on the Diapriidae and can be understood by reference to figure 1 2 VIII (3). HYMENOPTERA: PROOTOTRUPOIDEA 107. The whole of the abdomen posterior to the. propod.eum is called the , gaster (see Richards: Handbook far the Identification of British Insects Hymenoptera, 6 (1): 39): its first dol'Sal and first ventral segm.~nts are together modified to form a narrmv, stalk-like waist, referred to throqghout as the petiole. The petiole is always followed by a very large segment which, since it stands. out on size alone, is referred to as the ''large tergite ". In its simplest form, the gaster of both male and female is composed of eight visible tergites, the dorsum of the petiole being counted ·as tergite 1. The term "epomia" has not been used, as far as I am aware, in the taxonomy of the Proctotrupoidea. It is applied to a longitudinal ridge at the !:lide of the pronotum right ill. front . a)ld separates the side of the pro­ notum from the dorsal !:lurface, or collar (fig. 4). Another character that is being used here for the first t~e is the :qarrow, flange-like projection at the anterior margin of the mesoscutum in front of the lateral lobe. I have found it to be useful in sepl!J'ating groups of species in the genus Aclista (formerly Xenotoma s.l.). The antenna is regarded as being mad.e up of three P'Jrls, namely, a basal scape, a clearly differentiated pedicel and a flagellum. The genitalia of t~e male appear to offer valuable ~ and would certainly repay closer investigation. In this Handbook their value·a8,a means of separating species has been explored only in the ge~er&·'lrlffiij(a!@ ·Zygoto.. Figures 303-314 -are given only to show the~ of.Biiuctnte thaf e&n'be expected within the subfamily. · · · BIOLOGY. Little is known about the hosts oftM BE\).ytinae, though it is probable that · they are mostly parasites of Diptera, li .few species having peen bred from Mycetophilidae in rotting fungi._ Th~re is orie notable exception : Ismarus­ a genus sufficiently aberrant to be worthy of tribal rarik~has ~ bred as a hyperparasite from the cocooiiS or Dryinidae, themselves primEl.fy parasites of plant bugs (Homoptem,). , Species of Belytinae are obtained easily by sweeping and . ~h~y ~sho~d be sought where vegetation is lush a'nd varied. Woodlands whe~ "there ' is always an abundance of damp, decaying plant tissue seem to suit these . small parasites best. · ACKNOWLEDGMENTS. To M:r. A. W. Stelfox, in particular, I am deeply indebted not only(or the loan of a large and extremely rich collection of Irish and Scottish Belytinae, but also for the pa~ience with which he has , ~tllowed me for many Y¥A! to keep and study his · oollections. ·To Dr. Anton J:ansson of Orebro; Sweden, I am grateful for the prompt and generous way m.·which he has responded to all my requests for the loan of specimens. With his help and knowledge I have been able to' settle the identity of many of Thomson's species. Dr. Rem~ Malaise of the RikSmuseum, Stockholm, earns my very special tharik!l for arranging the loan of certain of Thomson's types. I am grateful also to Mr. J. F. Perkins of the BritiSh Museum (Nat. Hist.) for help with difficult points of nomenclature and for advice and encouragement at· all· times. BELYTINAE 3 Others who have helped me and receive my thanks are : Mr. V. H. Chambers, Mr. W. Daltry, Monsieur C. Granger, Dr. B. Petersen, Professor G. C. Varley and Dr. C. Ferriere. TYPES. The types of all new species are in the British Mruieum (Nat. Hist.) except where otherwise stated. All-species-that I have recognized from an examination of the types are marked with an asterisk. Family DIAPRUDAE (NW. European only). 1 Antenna of female with 14-15 segments, but nearly always with 15; rarely with 12 segments (Synacra) and then the gaster with 4 ring segments after the large tergite and a seventh and eighth beyond them, though these last 2 may hardly show a dividing suture ; antenna of male with 14 segments, the third (first flagellar) almost always emarginate ; only> in lamarus the fourth instead of the third antenna! segment modified, but this genus has the venation more or less typical of the subfamily (fig. 117). (Notaulices deeply impressed and complete except in Synacra (part), Anommatium and lamarus; hind wing with a closed basal cell except in Synacra (cf. fig. 1)) ...................... subfa.lDily BELYTINAE - Antenna of female with 11-13 segments, usually 12-13 ; when 12 are present, then either 3 ring segments after the large tergite (Diapria and related genera), or the frons ornamented with projections (Galesu8), .or the distal end of the sub­ costalis widely separated from the edge of the wing and the scutellar hollow (-apterous forms) more or less bipartite (Aneurrhynchus); antenna of male with 13-14 segments, the fourth (second flagellar), never the third, almost always sexually modified. (Hind wing without a closed basal cell) subfamily DIAPRIINAE (Not treated in this work). ' ~ubfamily'-, BELYTINAE. (__ KEY TO GENERA. \__ _~, (Femalea). Micropterous species ..................................................... 2 - Macropterous species ................................. ................... 7 2 Notaulices wanting -; antenna with 14 segments; apical segment of hind tarsus nearly as long as the 3 preceding segmentS together and with a long, powerful claw (fig. 57). (Entire -body fulvous yellow; eyes very small, clothed with a few long hairs ; flagellum much thickened towards apex, becoming more yellow apically, with the large, globose, apical segment the yellowest; apex of gaster clothed with very long, sparse, hairs ; 2 apical segments together forming a narrow, polished triangle with no clear line of separation between them) · Anommatlum-Forster (p.